[Ocfs2-tools-devel] [PATCH 1/1] Add a new method for exclusive option check in tunefs.ocfs2.

[Tao Ma]

In tunefs.ocfs2, we often have some exclusive options that can't
be done with others, and it is tedious when a new exclusive option
is going to be added since all other option checks have to be
modified accordingly.

So add a new method for this type of check so that any future
exclusive check will not touch those codes any more.

Signed-off-by: Tao Ma <tao.ma at oracle.com>
---
 tunefs.ocfs2/remove_slot.c |    5 +--
 tunefs.ocfs2/tunefs.c      |   56 ++++++++++++++++++++++++++++++++++++-------
 tunefs.ocfs2/tunefs.h      |   11 ++++----
 3 files changed, 55 insertions(+), 17 deletions(-)

diff --git a/tunefs.ocfs2/remove_slot.c b/tunefs.ocfs2/remove_slot.c
index 1e4238a..6da215d 100644
--- a/tunefs.ocfs2/remove_slot.c
+++ b/tunefs.ocfs2/remove_slot.c
@@ -755,9 +755,8 @@ errcode_t remove_slot_check(ocfs2_filesys *fs)
 	/* we don't allow remove_slot to coexist with other tunefs
 	 * options to keep things simple.
 	 */
-	if (opts.backup_super ||opts.vol_label ||
-	     opts.mount || opts.jrnl_size || opts.num_blocks ||
-	     opts.list_sparse || opts.feature_string) {
+	if (exclusive_option_check((char *)&opts.num_slots,
+				   sizeof(opts.num_slots))) {
 		com_err(opts.progname, 0, "Cannot remove slot"
 			" along with other tasks");
 		exit(1);
diff --git a/tunefs.ocfs2/tunefs.c b/tunefs.ocfs2/tunefs.c
index cf01110..9752192 100644
--- a/tunefs.ocfs2/tunefs.c
+++ b/tunefs.ocfs2/tunefs.c
@@ -324,9 +324,8 @@ static void get_options(int argc, char **argv)
 	 * options to keep things simple.
 	 */
 	if (opts.backup_super &&
-	    (opts.vol_label || opts.num_slots ||
-	     opts.mount || opts.jrnl_size || resize ||
-	     opts.list_sparse || opts.feature_string)) {
+	    exclusive_option_check((char *)&opts.backup_super,
+				   sizeof(opts.backup_super))) {
 		com_err(opts.progname, 0, "Cannot backup superblock"
 			" along with other tasks");
 		exit(1);
@@ -346,9 +345,8 @@ static void get_options(int argc, char **argv)
 	 * options to keep things simple.
 	 */
 	if (opts.list_sparse &&
-	    (opts.vol_label || opts.num_slots ||
-	     opts.mount || opts.jrnl_size || resize || opts.backup_super ||
-	     opts.feature_string)) {
+	    exclusive_option_check((char *)&opts.list_sparse,
+				   sizeof(opts.list_sparse))) {
 		com_err(opts.progname, 0, "Cannot list sparse files"
 			" along with other tasks");
 		exit(1);
@@ -359,9 +357,8 @@ static void get_options(int argc, char **argv)
 	 * options to keep things simple.
 	 */
 	if (opts.feature_string &&
-	    (opts.vol_label || opts.num_slots ||
-	     opts.mount || opts.jrnl_size || resize || opts.backup_super ||
-	     opts.list_sparse)) {
+	    exclusive_option_check((char *)&opts.feature_string,
+				   sizeof(opts.feature_string))) {
 		com_err(opts.progname, 0, "Cannot modify fs features"
 			" along with other tasks");
 		exit(1);
@@ -1738,3 +1735,44 @@ close:
 
 	return ret;
 }
+
+/*
+ * Some tasks of tunefs.ocfs2 can't be coexist with other options,
+ * so they are exclusive. Check whether they are other options
+ * initalized during get_options.
+ *
+ * NOTE:
+ * 1. opts must be memset to 0 for this function and actually it is.
+ * 2. there are some fields in opts that are not options, so remove
+ *    them from the check.
+ * 3. This function can't be used to check resize since it isn't a
+ *    number of opts.
+ */
+errcode_t exclusive_option_check(char *para, int size)
+{
+	int start;
+	int len = sizeof(opts);
+	char *content = NULL;
+
+	if (resize)
+		return 1;
+
+	/* We check from this field of opts. */
+	start = (char *)&opts.num_slots - (char *)&opts;
+	content = (char *)&opts.num_slots;
+	while (start < len) {
+		if (content == para) {
+			content += size;
+			start += size;
+			continue;
+		}
+
+		if (*content)
+			return 1;
+
+		content++;
+		start++;
+	}
+
+	return 0;
+}
diff --git a/tunefs.ocfs2/tunefs.h b/tunefs.ocfs2/tunefs.h
index 23bab70..f88435c 100644
--- a/tunefs.ocfs2/tunefs.h
+++ b/tunefs.ocfs2/tunefs.h
@@ -78,18 +78,18 @@ enum {
 };
 
 typedef struct _ocfs2_tune_opts {
+	char *progname;
+	char *device;
+	int prompt;
+	int verbose;
+	int quiet;
 	uint16_t num_slots;
 	uint64_t num_blocks;
 	uint64_t jrnl_size;
 	char *vol_label;
-	char *progname;
-	char *device;
 	unsigned char *vol_uuid;
 	char *queryfmt;
 	int mount;
-	int verbose;
-	int quiet;
-	int prompt;
 	int backup_super;
 	int list_sparse;
 	fs_options set_feature;
@@ -99,6 +99,7 @@ typedef struct _ocfs2_tune_opts {
 	int fd;
 } ocfs2_tune_opts;
 
+errcode_t exclusive_option_check(char *para, int size);
 void print_query(char *queryfmt);
 
 errcode_t remove_slots(ocfs2_filesys *fs);
-- 
1.5.3.2.g4f337